SEARCH for Diabetes in Youth (SEARCH) is an on-going, large, culturally diverse, multi-center and population-based epidemiological study of youth with diabetes. Initiated in 2000 and encompassing the major racial/ethnic groups in the U.S: non-Hispanic white, African-American, Hispanic, Asian-Pacific Islander, and American Indian, SEARCH was designed to estimate the prevalence, incidence and clinical presentation of diabetes in youth age < 20 years, by age, sex, race/ethnicity and diabetes type (SEARCH Registry Study). Beginning in 2002, SEARCH recruited a series of incident cohorts representative of the diverse racial/ethnic, socioeconomic and geographic base population, who were well-characterized through a variety of surveys, physical and laboratory assessments soon after diagnosis and followed them longitudinally (SEARCH Cohort Study). This proposal will continue longitudinal follow-up of the participants in the SEARCH Cohort Study to examine four Specific Aims: 1) To establish, compare and contrast the burden (prevalence, incidence, progression and clustering) of acute and chronic complications of diabetes, and explore the responsible risk factors and pathways among youth and young adults with type 1 and type 2 diabetes, 2) To explore, compare and contrast processes of care (including barriers to care and quality of care) and their influence on quality of life among youth with type 1 and type 2 diabetes, as they transition from pediatric to adult care, 3) to conduct surveillance of mortality including cause of death in the SEARCH cohort, and 4) to maintain, supplement and promote access to the SEARCH Cohort repository for biological specimens to conduct scientifically and logistically appropriate ancillary studies. Since there is an earlier onset and increasing rate of both type 1 and type 2 diabetes, the already high burden of diabetes to the individual and the nation will increase over time. Understanding the factors and pathways that contribute to this burden will provide the foundation to develop strategic interventions to limit individual morbidity and mortality and promote an effective, sustainable national health policy.